Anti-friction bearings

ABSTRACT

Anti-friction bearings for use between working members that may move relative to each other and wherein the anti-friction bearings include a plurality of bearing elements for supporting loads between the working members and in which one of the bearing elements is constantly in load bearing position while another of the load bearing elements moves between active and inactive positions and when in the active position shares the load with the bearing element in load bearing position.

United States Patent Geffner [451 Sept. 19, 1972 154] ANTI-FRICTIONBEARINGS [72] Inventor: Ted Gefiner, Merrick, N.Y.

[73] Assignee: The Barden Corporation, Danbury,

Conn.

[22] Filed: Oct. 15, 1971 [21] Appl. No.: 189,730

Related US. Application Data [63] Continuation of Ser. No. 28,719, April15, 1970, which is a continuation-in-part of Ser. No. 780,440, Dec. 2,1968, abandoned, which is a continuation-in-part of Ser. No. 586,151,Oct. 12, 1966, Pat. No. 3,446,540.

Brown ..308/6 3,446,540 5/1969 Geffner ..308/6 2,451,359 10/ 1948Schlicksupp.

2,452,117 10/1948 Ferger 2,503 ,009 4/1950 Thomson ..308/6 2,520,7858/1950 Schlicksupp ..308/6 2,655,415 10/ 1953 Briney ..308/6 3,005,66510/1961 Thomson et a1. ..315/207 3,265,449 8/ 1966 Jahn ..308/62,599,969 6/ 1952 Bajulaz ..308/6 C Primary Examiner-Edgar W. GeogheganAssistant Examiner-Barry Grossman Attorney-Sughrue et a1.

[57] ABSTRACT Anti-friction bearings for use between working membersthat may move relative to each other and wherein the anti-frictionbearings include a plurality of bearing elements for supporting loadsbetween the working members and in which one of the bearing elements isconstantly in load bearing position while another of the load bearingelements moves between active and inactive positions and when in theactive position shares the load with the bearing element in load bearingposition.

20 Claims, 7 Drawing Figures K 44 f /42 I I8b I0 :2 V I J :1- 5; 4 1 24I J J 2| ,38 34M -'-"---l8a P'A'TE'N'TED SEP 19 m2 SHEET 2 BF 3 INVENTORTED GEFFNER BY a @12 ATTORNEY P'ATE'N'TEDsEE 1 9 I972 3,692,371

SHEET 3 0F 3 INVENTOR. TED 6 EF F NE R ATTORNEYS ANTI-FRICTION BEARINGSCROSS-REFERENCE TO RELATED APPLICATIONS This is a continuation ofapplication Serial No. 28,719, filed April 15, 1970. r

This application continues, in part, material originally included inco-pending application Ser. No. 780,440, entitled Anti-FrictionBearings, filed on Dec. 2, I968, which continues, in part, materialoriginally included in application Ser. No. 586,l51, entitled Anti-Friction Bearings, filed on Oct. 12, I966, now U.S. Letters Pat. No.3,446,540, for which claim is made to all legal and equitable benefitswhich are able to be derived therefrom.

BRIEF SUMMARY OF THE INVENTION This invention relates to improvements inanti-friction bearings that may be employed between workpieces that moverelative to each other.

There has long been a problem in the art of anti-friction bearings ofincreasing their effective and usable life. Attemptsat this have beendirected to the use of different and exotic bearing surfaces and loadbearing elements that would tend to withstand high loads. Unfortunately,these have resulted'in higher and unacceptable manufacturing costs.Other attempts have included the provision of pathways that have enabledthe bearings to move and traverse the work members in the mannerexemplified by the U.S. Letters Pat. No. 2,451,539. In such instances,the traversing bearing elements wear a groove in the surfaces in whichthey bear and thus result in shortened bearing life.

In applicants co-pending application, as mentioned above, traversingbearing elements move between active and inactive positions, thuseliminating and relieving the load bearing forces from constantapplication to such bearing elements, hence increasing their effectivelife. Such movement of the bearing elements produces a correspondingmovement of an intermediate bearing member whose surfaces are constantlychanging and which, in turn, provides a support for other changingsupporting bearing elements. This arrangement of constantly changingsurfaces results in increased life and improved load carryingcharacteristics.

The desideratum of the present invention is to provide bearings ofimproved load carrying characteristics and increased life which are lessexpensive than those of comparable size known heretofore for performingthe same purposes. Furthermore, the present invention enables suchbearings to position the loads between working members that may bepermitted to move rectilinearly or rotatively. l

Further objects and features of the invention reside in the provision ofbearings in which loads will be transmitted over large and constantlychanging bearing surfaces so that such loads are distributed moreefficiently and shared more readily by a larger number of load bearingsurfaces at any given moment than has been done heretofore.

Other and further objects of this invention reside in the structures andarrangements hereinafter more fully described with reference to theaccompanying drawings.

FIG. 1 is a view of an anti-friction bearing constructed according tothe invention and with portions thereof broken away to illustrate itsworking details,

FIG. 2 is a cross-section of FIG. l taken along lines 2-2,

FIG. 3 is a view of a modified anti-friction bearing constructedaccording to the teaching of the invention, life.

FIG. 4 is a cross-section of FIG. 3 taken along lines FIG. 5 is-aperspective view of a spacer member employed in the embodiment of FIGS.3 and 4,

FIG. 6 is a perspective view of another embodiment with portions thereofbroken away, and

FIG. 7 is a perspective view of another embodiment with portions thereofbroken away. I

DETAILED DESCRIPTION Referring now to FIGS. 1 and 2 of the drawing,there is disclosed an anti-friction bearing generally identified by thenumeral 10. The anti-friction bearing 10 may be adapted to be positionedalong or for relative movement about a working piece, shown in thedrawing for illustrative purposes only as a shaft 12. It will beapparent to those skilled in the art that the working piece 12 may be ofany desired shape and configuration since its details form no part ofthis invention.

The bearing 10 comprises a housing that is designated generally by thenumeral 14. The housing 14 is shaped in the form of an annulus forconvenient circumposition about the workpiece shaft 12. Thus, if theworkpiece 12 were of a different shape, the housing would have acorresponding configuration. The housing 14 comprises a retainer element16 and a sleeve 18. The sleeve 18 is connected to the retainer 16 forconjoint rotation and co-linear movement by end caps, 20,

only one of which is illustrated in FIG. 1.

The composite housing 14, comprising the retainer 16, the sleeves 18 andthe securing end caps 20, defines an integral structure which moves as aunit. Although the housing 14 is formed of five parts the same shouldconstitute no limitation upon the invention. The effect of the assemblyis to result in a single, easily assembled, yet inexpensivelymanufactured integral housing.

Prior to assembly, the housing I4 is provided with one or more bearingpaths that are of endless construction. These endless bearing paths areshown in FIGS. 1

and 2 of the drawing as spaced circumferentially about and definedwithin the housing 14. The bearing paths are endless in detail in thatthey return to a starting point, whatever moves therein, and they arecompletely formed within the housing confines. Each such endless bearingpath includes an active portion 22 and an inactive portion 24. Eachactive portion 22 is operatively connected with the inactive portion 24of its respective endless path by a smooth curved end 26 at each end ofthe bearing path. The smooth curved ends 26 define an uninterruptedconnection between the active and inactive portions 22 and 24 of each ofthe endless pathways. The curveds 26 thus terminate each such portion 22and 24 to effect a smooth merger between such portions and along whichload bearing elements, to be described, may move unencumbered andunobstructed.

The inactive portion 24 of each of the endless bearing paths is spacedradially outward of the related active portion 22 of its respectiveendless bearing path. It will be recognized further that the inactiveand active portions 24 and 22 respectively of each endless path isrelatively angularly spaced about an arc of the circumference of thehousing 14. Thus, the active and inactive portions 22 and 24 of eachendless bearing path is offset arcuately with respect to each other andsmoothly connected in such offset relationship by the merging curvedsurfaces 26 positioned at the opposite ends of each endless bearingpath.

The bearing structure is adapted to retain-at least one or more rollablebearing elements for movement within and along the endless bearingpaths. In FIGS. 1

and 2, the rollable bearing element may include a set of a plurality ofspherically shaped or ball bearing elements. Although all theloadbearing elements that may fill and are movable in each endlessbearing path may be of the same size and shape, for convenience ofdescription and illustration they will be differently numbered toidentify their functions as they move into different portions of theirendless pathways. The load bearing elements illustrated in FIGS. 1 and 2that are positioned within the inactive portion24 of the endless bearingpaths are identified by the numeral 28 while the bearing elementsidentified 30 are shown positioned within the active portion 22 of theendless bearing paths.

The active portion 22 of each endless bearingpath is formed as a part ofan elongated radially directed slot 23 within the retainer element 16,but terminating short of the ends of the retainer element. The slot 23extends radially completely through the retainer 16 from the inner tothe outer surface thereof as is more easily seen in FIG. 2. Positionedwithin the radial outer portion of the slot 23, remote from but incommunication with the bearing elements at 30, is a second bearingelement 32. Each bearing element 32 is the form of a roller that extendsacross the complete length of the outer portion of slot 23 and thus ispositioned in overlying relationship with each of those load bearingelements 30 that are in the active bearing position within the housing14. The bearing elements 28 in the inactive or non-load bearing positionwithin the inactive portion 24 of the endless paths is locatedalternately and circumferentially spaced between adjacent slots 23 andthe roller bearing elements 32.

The roller bearing elements 32 are narrowed at their opposite ends andtaper to substantially but not necessarily completely to a point 34 asis shown in FIG. 1. The narrowing ends 34 of the bearing elements 32 areengaged with those bearing elements 30 located in the portion 22 as theballs 30 move along the active load bearing portion 22 of the respectiveendless bearing path and between the inactive portion 24 of the samepath. This is illustrated more fully in the cut-away portion of FIG. 1wherein the ball bearing elements depicted at 36 and moving in thecurved ends 26, are positioned in engagement with the narrowing portion34 of the roller bearing element 32.

By conveniently designing the slot 23 as a through radial opening in theretainer 16, both the active portion 22 of the endless bearing pathwayand the accommodation for the roller bearing elements 32 are at onceprovided. The formation of the smooth curved merging surface 26 at theends of the endless bearing paths to connect the portions 22 and 24together may also be formed conveniently in the retainer 16 and in theouter sleeve 18. The outer sleeve 18 is easily shaped and formed forcircumposition about the retainer by separating it into two halves 18aand 18b. After the retainer element 16 and the sleeve halves 18a and 18bare manufactured, they are assembled quickly and easily about each otherafter the load bearing balls or spherical elements are inserted into theendless bearing paths. In the drawings, it will be seen that the ballbearing elements fully pack their respective endless paths. The rollerbearing elements 32 are retained and mounted within the outer radialportions of the slots 23 immediately in engagement with the balls in theactive portion 22 of the respective endless bearing path.

The whole housing 14 is then assembled as an integral unit by theapplication of endcaps 20 to opposite ends to connect the sleeve halves18a and 18b to the retainer element 16 covering relation therewith. Itwill be noted that the composite covering sleeve halves are providedwith a continuous elongated slot 38 which accommodates a respectiveroller bearing element 32 so the same extends and projects radiallyoutward beyond the housing 14 into a constant load bearing position.Thus, the roller bearing elements 32 are constantly retained in anactive load bearing relationship to the housing 14 and are in loadbearing engagement with those bearing elements traversing the respectiveendless bearing path to and from the active bearing position 30 and toand from the active portion 22.

The present anti-friction bearing 10 is adapted to be used betweenworkpieces that may move linearly relative to each other and/orrotatively relative to each other. Such workpieces may be of any shapeand form consequently, the anti-friction bearing 10 will becorrespondingly configured. Inasmuch as the description has been deemedmost easily described for use with a shaft 12, the bearing 10 has beencorrespondingly made cylindrical in shape. Hence, the bearing 10 will beadapted for use with a further workpiece 40 illustrated in dash lines inFIGS. 1 and 2. The workpiece 40 may be retained in position about thebearing 10 of the present invention by the application of snap rings 42within annular grooves 44 provided at opposite ends of the bearing.

During relative rectilinear movement of the shaft 12 and the workpiece40 secured to and about the bearing 10, the bearing elements at 30 inthe active load-bearing portion 22 of each respective endless bearingpath engage the inner workpiece 12 while the other bearing element 32 ofeach bearing path engages the outer workpiece 40. At such time, thebearing elements at 30 in the active load bearing position, also engagealong the radial inner surface of the roller 32 so there is a transferof load between the numerous load bearing elements 30 in theload-bearing position and the respective roller 32 which they engage. Asshown in FIG. 2, the longitudinal axis of each of the rollers 32 ispositioned to intersect the load path vector extending through thepoints of contact of the balls 30 with each roller 32 and the wordpiece12 when the balls 30 are in the load bearing position.

As the two workpieces l2 and 40 move linearly relative to each other,the balls in each endless bearing path tend to roll in a directionlongitudinally of their respective bearing path. Thus, there is aprocession of load bearing elements from the active bearing position 30in the portion 22 of the endless bearing path to the inactive bearingpath position 28 of the inactive portion 24 of the same bearing path.The height of the inactive portion 24 is visibly greater than the sizeor diameter of the bearing elements moving through such portion 24 sothat each such bearing element in position 28 is not in load-bearingrelationship with any load applying structure, and, therefore, they arein an inactive position.

As the balls or bearing elements move from their active load-bearingposition 30 to their inactive non-loadbearing position 28, they passthrough and along the smooth curved end portion 26 where they remain incontact with the narrowing end 34 of their respective elongated rollerbearing element 32. During their movement along the curved portions- 26and of their endless path, the bearing elements move at an angle to thedirection of linear movement of the housing 14. This is so because eachcurved portion 26 is angled between the active portion 22 and inactiveportion 24 of the endless bearing path. Because the roller ends 34 arenarrowing in form the angle of attack and engagement' of the ballsmoving in portions 26 changes progressively with relation to the roller32. This varying and changing angular relationship of the balls engagingthe narrowing ends of the rollers 32 causes the engaged roller 32 torotate about its axis and thus presents a continually changing surfacefor load bearing engagement with the balls moving into and out of theactive load bearing position 30 and into the active portion 22 of theendless bearing path.

It should be clear to those skilled in the art that as a consequence ofthe continuous change and movement of the bearing elements or the ballsfrom the load bearing position 30 to the non-load bearing position 28 intheir endless position bearing paths, there is a continuousredistribution of forces and loads against different and changing onesof such ball bearing elements. Further, as the bearing elements movealong the curved merging surfaces 26 at the opposite ends of theirendless bearing path, they apply a rotational force to the narrowingends of the rollers 32 which cause the rollers to rotate and changetheir surfaces presented for engagement with the balls 30 at the activeload bearing position. By this method, no one surface of the bearingelements 30 or 32 ever absorbs or supports a load for a time more than afraction of their rotation. Rather, the surfaces of the load bearingelements in load bearing position are constantly changing therebyincreasing their effective life.

When the bearing is employed between relatively rotatable workpiecesmuch the same beneficial result occurs. In the case where the workpiecesl2 and 40 are relatively rotatable, the roller bearing elements 32engage the outer workpiece 40 and are caused to rotate within thehousing 14. As the roller elements 32 rotate in their load bearingposition, they impart a rotational movement to the engaging ball bearingelements in position within the active portion 22. This causes the ballbearing elements to rotate also. In addition, the ball bearing elementsin position 30 rotate because of their engagement with the innerworkpiece 72 with which they are in load bearing engagement. Thus, theballs and rollers engaging each other equally distribute their loadsacross many continually changing surface.

In addition, however, the rotation of the roller 32 causes the balls 30to process within their endless hearing path by engaging the balls 36 inthe curved portions 26 of the endless bearing path. This engagement bythe narrowing end portions of the rollers 32 with the balls 36 in thecurved portions 26 causes the balls 36 to move angularly along theendless bearing path. As a consequence, the balls in the endless bearingpath move between their active load bearing position 30 in portion 22and their inactive, non-load bearing position 28, within the portion 24.Thus, the balls are in continual movement within their endless bearingpath even though the workpieces are movable rotatively relative to eachother. As a result, the surfaces supporting the loads between theworkpieces are continually changing and equally distributing the workforces between the sets of bearing elements whose surfaces arecontinually in motion.

The embodiment shown in FIGS. 3, 4 and 5 is substantially the same asthat previously described. The present embodiment will be identified bynumerals in the series while the digits thereof will correspond toelements previously described in the prior embodiment 10.

Referring to FIGS. 3, 4 and 5, the anti-friction bearing there disclosedis generally identified by the numeral 110. Bearing is adapted to bepositioned with respect to a workpiece, hereshown for illustrativepurposes only as a circular shaft 112. The'housing generally identifiedby the numeral 114 is a composite but unitary structure comprising aretainer element 1 16 and an outer sleeve 118.

The details of the retainer element 116 are not too dissimilar from thatof the prior embodiment. The retainer 116 is of a one-piece constructionhaving defined therein a plurality of circumferentially spaced radiallydirected slots 123. Each of the slots 123 defines an active portion 122along its radially inner part which forms one portion of an endlessbearing path that includes an arcuately offset inactive portion 124. Aspreviously described, the inactive portion 124 and the active portion122 each terminate at their opposite ends in smoothly curved ends whichfunction as merging portions 126. The merging portions 126, at each endof the portions 122 and 124, complete the endless bearing path alongwhich a rollable bearing element or a plurality of such elements areadapted to move between load bearing position and non-load bearingposition.

' When the rollable bearing element is in load bearing position in itsendless bearing path, it is identified by the numeral 130. As previouslydescribed, the bearing element in the load bearing position is locatedwithin the portion 122 of the endless bearing path. However, as thebearing element moves in the endless bearing path to its non-leadbearing position identified by the number 128, it is in the inactiveportion 124 of the bearing path. The inactive portion 124 is visiblylarger in size than the bearing element positioned at 128 and,therefore, each such bearing element is free of any load bearingrelationship.

This manner of operation has been described with respect to the priorembodiment 10. In practice, the endless bearing path is fully filledwith as many rolling bearing elements as it can accommodate. Suchbearing elements are shown as balls or spheres because they circulatemore freely and present new load bearing surfaces more readily as theymove along the portions 122, 126 and 124 which comprise each endlessbearing path.

Positioned within the outer portion of each radial slot 123 is a bearingelement 132. The bearing element 132 is shown in the form of anelongated roller, the opposite ends of which are provided withprogressively narrowing surfaces 134 that approximate, but need notfully approach a point. The rollers 134 completely fill the length ofthe elongated slot 123, so that their narrowing ends 134 are engaged inprogressively changing annular relationship with the bearing elementsmoving along the respective endless bearing path at the smoothly curvedends 126. For convenience of reference, and identification, such rollersare identified by the numeral 136.

The rotative cooperation between the load bearing elements positioned at130 within the active portion 122 and the bearing element 132 within therespective slot 123, is the same as previously described in connectionwith the embodiment 10. Similarly, the changing angle of attack andengagement between the bearing elements positioned at 136 within thecurved ends 126 and the narrowing ends 134 of the respective bearingelements 132 is the same as described with respect to the priorembodiment 10.

The present embodiment 110 is essentially the same in operation as theembodiment 10 previously described and, therefore, parts similarlynumbered with the 10s digits will perform in the same manner. Hence, itwould be redundant and surplussage to repeat the description of theoperation of the embodiment 10 as it applies to the present embodiment 110.

In the present embodiment it will be noted that the outer sleeve 118 isof a single or one-part construction that fully encompasses and 'ispositioned about the retainer 116. The sleeve 118 is preferablyimperforate indetail and, unlike the embodiment 10, it retains theroller bearing elements 132 within their respective slots 123 by fullycovering the same and providing a smooth uninterrupted interior surfaceagainst which the bearing elements 132 may roll.

The sleeve 118, being of one piece construction, is rolled or turnedover at its opposite ends 120 to provide for relative rotationalengagement with corresponding end surfaces of the retainer 116. In thepresent embodiment 110, the sleeve 118 is adapted to have relativerotation with respect to the retainer 116 whereas in the priorembodiment 10 the two-part sleeve 18 was adapted to be secured forconjoint movement with the retainer 116. Thus, although the sleeve 118may move rotationally relative to the retainer 116 it is secured forconjoint linear movement with the retainer 116 and thus completes theunitary and integral housing 114.

Inasmuch as the outer sleeve 118 is circumposed radially outward of thebearing elements 132, and does not accommodate the same within theconfines thereof, the radial extent of the retainer 116 is increased tofully accommodate the roller bearing elements 132 and the ball bearingelements 130 within the radial slots 123. In consequence, the radialextent of the inactive portion 124 of each endless bearing path isgreater in the present embodiment 110 than it was in the priorembodiment 10. In practice, it has been found that the greater radialextent of the portion 124, in which the non-load bearing elements arepositioned at 128, must be shortened otherwise there would be toomuchfree movement and play permitted the bearing elements. Hence, thebearing elements at the position 128 would tend to bunch together, movetoo freely and loosely within the endless bearing path, and thus createapossible wedging action between themselves that will prevent suchbearing elements from moving smoothly from the inactive position 128 tothe active position 130.

To obviate the difficulties that may be created by the radial elongationof the inactive portion 124 of the endless bearing path, there isprovided a shim or spacer means generally identified by the numeral 146and more fully shown in FlG. 5. The spacer means functions as a shim toshorten the radial extent of the inactive portion 124 of the endlessbearing path. lts both thickness 148 is sufficient to retain the bearingelements at the position 128 in proper alignment with each other and insmooth, free circulating relationship in the portion 124. The spacermeans 146 terminates in curved ends 150 that are adapted to be locatedin overlying relationship with the curved ends 126 of each endlessbearing path.

There is provided one of each of the spacer means 146 for insertion intothe outer radial part of the inactive portion 124 of each endlessbearing path. When so positioned, the curved ends 150 overlie and serveto guide the ball bearing elements positioned at 136, in the curved ends126 of theendless bearing path, for smooth rolling movement beneath andfor engagement with the narrowing angular end 134 of each roller bearingelement 132. Thus, the spacer means 146 functions to shorten the radialheight of portion 124. This reduces the radial space between the bearingelements positioned at 128 and those at 130 so the relative radialdistance between them is not so great as to inhibit the free rollingcirculation of the bearing elements through and along the endlessbearing path.

inasmuch as the sleeve 118 is rotationally joinedto the retainer 1 16and forms an integral part of the housing 114, it is possible to treatthe sleeve 118 as a substitute for the workpiece 40 described withrespect to the embodiment 10. However, if desired, a further workpiecemay be secured to the outer surface of the sleeve 118, for rotationtherewith. 1

The operation of the present embodiment is essentially the same as thatof the embodiment l0 previously described. During relative rectilinearmovement of the workpiece 112 with respect to the sleeve 118, the ballbearing elements positioned at in the endless bearing paths will engagethe workpiece 112 and will support the loads transmitted to the bearing110. Such loads are, in turn, transmitted and distributed equally to theroller bearing elements 132 which engage, in load bearing relationship,the sleeve 118 that may support a further load applying workpiece.

During relative rectilinear movement of the workpieces the bearingelements move to and from their load bearing positions 130, and as theymove along the ends 126 of the endless bearing paths, their angle ofattack with respect to and engagement with the narrowing ends of thebearing elements 132 change. This produces a rotational force that isapplied not only to the ball bearing elements as they move along theposition 136, but also against the roller bearing elements 132. As aconsequence, the balls revolve to present changing surfaces forengagement with the workpiece 1 12 and roller 132, and the roller 132rotates to present changing surfaces for engagement with the inner sur--face of the sleeve 118. Hence, even though the workpieces moverectilinearly relative to each other, the bearing elements continuallypresent changing bearing surfaces, which results in a bearing structurehaving a longer effective life span.

During relative rotation of the workpieces, the bearing elements in theposition 130 rotates at one-half the rotational speed of the workpiece112 which they engage. In consequence, their wear is materiallydecreased. However, and in addition, because of the rotation of thebearing elements 132, the ball bearing elements at 136 are forced tocirculate in their endless bearing paths and thereby continually presentnew bearing surfaces for supporting the loads between the relative loadapplying workpieces.

Those skilled in the art will recognize that the retainer elements 16and 116 can be made of easily and inexpensively formed materialsinasmuch as they merely are retainers that are not required to supportexcessive forces. In consequence, such retainers may be conveniently andinexpensively manufactured from well known plastic materials. Much thesame is true with respect to the spacer means 146 included within theinactive portion 124 of each of the endless bearing paths.-

The embodiment shown in FIG. 6 is substantially the same as thatpreviously described and shown in FIGS. 3, 4 and 5. The presentembodiment will be identified by numerals in the 200 series while the sdigits thereof will correspond in structure and function with elementspreviously described.

Reference is now made to FIG. 6 wherein the antifriction bearing theredisclosed is generally identified by the numeral 210. Bearing 210 isstructured much in the arrangement of bearing 110 except that the radialslots 223 contain at least one or more bearing elements 232, hereidentified for ease of reference by the numerals 232a and 232b. Thebearing elements 232a are positioned at the radially outermost extent ofthe slots 223 while the bearing elements 232b are positioned between orintermediate the bearing elements 230 and 2320. The outermost andintermediate bearing elements 232a and 232b extend for substantially thefull length of their respective slots 223 and the intermediate bearing"elements 232b may be narrowed (not shown) as is shown and described asat 34 and 134 in the prior embodiments.

The use of the plurality of bearing elements 232 serves to supportgreater loads transmitted between the shaft 212 and the relativelyrotatable and rectilinearly movable outer sleeve 218. Although thepresent embodiment of FIG. 6 compares with that of FIGS. 3, 4 and 5,those skilled in the art will readily recognize that the teachingthereof is equally applicable to the embodiment of FIGS. 1 and 2. 1

The embodiment of FIG. 7 incorporates the teaching of the aforedescribedembodiments except that it illustrates their use in a planar or flattype anti-friction bearing. Because of the similarities in operative andstructural details the elemental details will be identified by numeralsin the 300 series with the l0s digits thereof corresponding in structureand function with those previously described.

The flat-type anti-friction bearing of FIG. 7 is more easily identifiedas a flatway" because of its ability to support and transmit loadsbetween load bearing members that move in flat or substantially planarpaths. The bearing of FIG. 7 is generally identified by the numeral 310and includes a housing generally identified by the numeral 314 havingsubstantially planar or flat upper and lower surfaces and in whichthehousing may be fixed to one load member. The housing 314 comprises aretainer structure delineated by the retainer elements 316 that arespaced from outer walls 317 to define the slots 323 in which the activebearing elements 330 and the plurality of bearing elements 332 arecontained and project beyond the lower planar surface of the housing forengagement with a load member therebeneath.

The active ball bearing elements move in their endless paths defined bythe slots 323 and 324 connected by the merging portions 326 along whichthe bearing elements 336 are guided for movement into and out ofengagement with the intermediate bearing element 332b that is inconstant rolling engagement with the outer roller bearing element 332athat project upward and beyond the upper planar or flat surface of thehousing for engagement with the load member thereabove. The intermediatebearing elements 332a extend for substantially the length of the slots323 and their bearing surfaces project or are located beyond the limitsof the retainer elements 316 and spaced walls 317.

The assembly of the housing is completed by a cap or cover plate 352that is substantially L shaped such that its narrow body fits betweenthe retainer elements 316 to close the inactive portions324 of theendless bearing paths. The enlarged ends of the cover plate 352 nestlewithin correspondingly shaped seats 354 at opposite ends of the housing314 and are fastened in such position by any convenient means 356 thatmay be mated into openings 358. The enlarged ends of the cover plate 352restricts the size of the slots 323 so as to prevent the loss ordisplacement of the roller 324a therefrom until such plate isdeliberately removed.

The present bearing 310 may be utilized to permit relative flat orplanar type movement in X and Y directions as shown in the drawing orany relative component movement. This is accomplished by connecting orfastening the housing 314 to one load bearing member and placing anotherload bearing member on the exposed surfaces of the bearing elements332a. During relative movement between the load bearing members orworkpieces, the roller bearing elements will move along their endlesspaths between their active load bearing positions in the slot 323 andtheir inactive or non-load bearing positions in slots 324. There is acontinuous exchange of bearing surfaces that results in a more efficientand longer lasting bearing.

While there have been shown and described and pointed out thefundamental novel features of the invention as applied to severalpreferred embodiments thereof, it will be understood that variousomissions and substitutions and changes in the form and details of thedevices illustrated and in their operations may be made by those skilledin the art, without departing from the spirit of the invention. it isthe intention, therefore, to be limited only as indicated by the scopeof the claims appended hereto.

What is claimed is:

1. in a bearing for a workpiece,

a housing,

an endless bearing path defined in said housing,

said path including an active portion and an inactive portion,

a plurality of balls movable in and along said bearing path between saidactive portion wherein said balls are in load bearing position and saidinactive portion wherein said balls are in non-load bearing position,and

a roller rotatably mounted in said housing in a load bearing position,

certain of said balls being in load bearing engagement with said rollerwhen said balls are in their load bearing position, said roller beingrotatable in response to the movement of said balls in said path, andthe longitudinal axis of said roller being positioned to intersect theload path vector extending through the points of contact of certain ofsaid balls with said roller and the workpiece when said balls are in theload bearing position.

2. In a bearing as in claim 1,

said housing having opposed surfaces,

said balls in said active portion projecting from one of said surfaces,and

said roller projecting from the other of said opposed surfaces.

3. In a bearing as in claim 1,

a plurality of bearing paths each being relatively spaced in saidhousing,

said active and inactive portions of each of said bearing paths beingrelatively spaced at different levels in said housing,

a plurality of balls movable in each of said bearing paths,

a plurality of rollers rotatably mounted and relatively spaced in saidhousing between said inactive portions of adjacent bearing paths, eachof said rollers being mounted in a load bearing position with respect toone of said paths, and said balls in each path being in load bearingengagement with the adjacent roller when they are in load bearingposition.

4. In a bearing as in claim 3,

said housing being an annulus, and

said inactive portion of each of said paths being angularly and radiallyspaced from said active portion of the respective paths.

5. In a bearing as in claim 4,

said housing comprising a retainer in which said bearing paths aredefined,

a sleeve rotatably connected to said retainer for movement relative tosaid retainer,

and spacer means in each of said inactive portions of each of saidbearing paths.

6. In a bearing as in claim 4,

said housing comprising a retainer and a sleeve in which said bearingpaths are defined,

and means connecting said sleeve and retainer together for conjointmovement.

7. ln a'bearing as in claim 1,

spacer means in said inactive path portion for guiding said balls towardsaid active path portion wherein they are in load bearing position inengagement with said roller.

8. In a bearing as in claim 1,

the longitudinal axis of said roller being substantially in radialalignment with an axis extending through the centers of said balls whenthey are in load bearing position.

9. In a bearing,

first and second load bearing elements,

a movable housing in which said first and second load bearing elementsare retained,

a path defined in said housing in which said first load bearing elementmoves at an angle to the direction of movement of said housing betweenload bearing and non-load bearing positions,

said path including a portion thereof into which said first load bearingelement moves when in load bearing position and a portion thereof intowhich said first load bearing element moves when in nonload bearingposition, and a a plurality of said secot'id load bearing elements beingrotatably retained in said housing in constant load bearing position,one at said second load bearing elements being engageable between saidfirst load bearing element and another of said second load bearingelements when said first load bearing element is in said load bearingposition,

said first and said one of said second load bearing elements beingengaged as said first load bearing element moves to and from the loadbearing position, and the movement of said first load bearing elementcausing said second load bearing elements to rotate in their loadbearing position.

10. In a bearing as in claim 9,

said first load bearing element being a ball and said second loadbearing elements being rollers movable with and in the direction of saidhousing,

said housing including a plurality of said paths defined therein,

a plurality of said balls movable in each of said paths,

each of said paths having a portion thereof positioned at an angle tothe direction of movement of said housing to direct said balls formovement at an angle to the direction of movement of said housing,

and at least certain ones of said plurality of balls being engaged withone of said rollers as said balls move in their respective path portionwhen in load bearing position.

11. A bearing comprising a housing a plurality of endless ball pathsdefined in said housa plurality of balls movable in each of said ballpaths between load bearing position and non-load bearing position,

a plurality of rollers rotatably mounted and spaced in said housing,with only one roller for each of said ball paths in rolling engagementwith the balls in load bearing position in its respective ball path,

and a portion of each of said paths locating said balls in non-loadbearing position in said housing and out of engagement with the rollersin their respective paths.

12. A bearing as in claim 11,

there being at least two rollers for each of said ball paths with one ofsaid two rollers spaced from said balls in load bearing position andanother of said rollers engaged between said one roller and said ballsin load bearing position.

13. A bearing as in claim 12,

said housing having relatively flat opposed surfaces,

certain of said balls projecting through one of said surfaces and one ofsaid plurality of rollers in the respective path of said projectingballs projecting through the opposed surface.

14. A bearing as in claim 1 1,

said housing comprising a retainer and a sleeve connected for conjointrotation and in which said paths are defined.

15. A bearing as in claim 11,

said housing comprising a retainer in which said paths are defined,

and a sleeve rotatably connected to said retainer.

16. A bearing as in claim 11,

said one roller for each of said ball paths having a tapered end engagedby said balls in their respective ball paths as said balls move into andout of load bearing position.

17. A bearing as in claim 1 l,

the longitudinal axis of said one roller being intersected by the loadpath vector extending through the points of contact of said balls withsaid one roller and the workpiece for the bearing when said balls are inthe load bearing position.

18. A bearing comprising a housing having two substantially flatsurfaces and a retainer means defining an endless bearing path, saidpath including load bearing and non-load bearing portions,

a plurality of first bearing elements,

a plurality of rotatable second bearing elements,

said first bearing elements being movable in said bearing path between aload bearing position wherein they project from one of said housingsurfaces and a non-load bearing position,

and one of said second bearing elements being engaged between said firstbearing elements in load bearing position and another of said secondbearing elements having a surface thereof projecting from the other ofsaid housing surfaces, said-one second bearing element being free ofengagement with said first bearing elements in the non-load bearingposition.

19. In a bearing,

a housing,

an endless bearing path defined in said housing,

said path including an active portion and an inactive portion,

a plurality of first bearing elements movable in and along said bearingpath between said active portion wherein the same are in load bearingposition and said inactive portion wherein the same are in non-loadbearing position,

a second bearing element in said housing,

and certain of said first bearing elements being in load bearingengagement with said second bearing element when said first bearingelements are in their load bearing position,

said second bearing element comprising at least two freel rotatableroller bearing elements, one 0 said two roller bearing elements beingengaged between certain of said first bearing elements in the loadbearing position and the other of said roller bearing elements.

20. In a bearing as in claim 19,

said housing having two relatively flat surfaces,

certain of said first bearing elements projecting through one of saidsurfaces and said other of said second bearing elements projectingthrough the other of said surfaces.

1. In a bearing for a workpiece, a housing, an endless bearing pathdefined in said housing, said path including an active portion and aninactive portion, a plurality of balls movable in and along said bearingpath between said active portion wherein said balls are in load bearingposition and said inactive portion wherein said balls are in non-loadbearing position, and a roller rotatably mounted in said housing in aload bearing position, certain of said balls being in load bearingengagement with said roller when said balls are in their load bearingposition, said roller being rotatable in response to the movement ofsaid balls in said path, and the longitudinal axis of said roller beingpositioned to intersect the load path vector extending through thepoints of contact of certain of said balls with said roller and theworkpiece when said balls are in the load bearing position.
 2. In abearing as in claim 1, said housing having opposed surfaces, said ballsin said active portion projecting from one of said surfaces, and saidroller projecting from the other of said opposed surfaces.
 3. In abearing as in claim 1, a plurality of bearing paths each beingrelatively spaced in said housing, said active and inactive portions ofeach of said bearing paths being relatively spaced at different levelsin said housing, a plurality of balls movable in each of said bearingpaths, a plurality of rollers rotatably mounted and relatively spaced insaid housing between said inactive portions of adjacent bearing paths,each of said rollers being mounted in a load bearing position withrespect to one of said paths, and said balls in each path being in loadbearing engagement with the adjacent roller when they are in loadbearing position.
 4. In a bearing as in claim 3, said housing being anannulus, and said inactive portion of each of said paths being angularlyand radially spaced from said active portion of the respective paths. 5.In a bearing as in claim 4, said housing comprising a retainer in whichsaid bearing paths are defined, a sleeve rotatably connected to saidretainer for movement relative to said retainer, and spacer means ineach of said inactive portions of each of said bearing paths.
 6. In abearing as in claim 4, said housing comprising a retainer and a sleevein which said bearing paths are defined, and means connecting saidsleeve and retainer together for conjoint movement.
 7. In a bearing asin claim 1, spacer means in said inactive path portion for guiding saidballs toward said active path portion wherein they are in load bearingposition in engagement with said roller.
 8. In a bearing as in claim 1,the longitudinal axis of said roller being substantially in radialalignment with an axis extending through the centers of said balls whenthey are in load bearing position.
 9. In a bearing, first and secondload bearing elements, a movable housing in which said first and secondload bearing elements are retained, a path defined in said housing inwhich said first load bearing element moves at an angle to the directionof movement of said housing between load bearing and non-load bearingpositions, said path including a portion thereof into which said firstload bearing element moves when in load bearing position and a portionthereof into which said first load bearing element moves when innon-load bearing position, and a plurality of said second load bearingelements being rotatably retained in said housing in constant loadbearing position, one at said second load bearing elements beingengageable between said first load bearing element and another of saidsecond load bearing elements when said first load bearing element is insaid load bearing position, said first and said one of said second loadbearing elements being engaged as said first load bearing element movesto and from the load bearing position, and the movement of said firstload bearing element causing said second load bearing elements to rotatein their load bearing position.
 10. In a bearing as in claim 9, saidfirst load bearing element being a ball and said second load bearingelements being rollers movable with and in the direction of saidhousing, said housing including a plurality of said paths definedtherein, a plurality of said balls movable in each of said paths, eachof said paths having a portion thereof positioned at an angle to thedirection of movement of said housing to direct said balls for movementat an angle to the direction of movement of said housing, and at leastcertain ones of said plurality of balls being engaged with one of saidrollers as said balls move in their respective path portion when in loadbearing Position.
 11. A bearing comprising a housing a plurality ofendless ball paths defined in said housing, a plurality of balls movablein each of said ball paths between load bearing position and non-loadbearing position, a plurality of rollers rotatably mounted and spaced insaid housing, with only one roller for each of said ball paths inrolling engagement with the balls in load bearing position in itsrespective ball path, and a portion of each of said paths locating saidballs in non-load bearing position in said housing and out of engagementwith the rollers in their respective paths.
 12. A bearing as in claim11, there being at least two rollers for each of said ball paths withone of said two rollers spaced from said balls in load bearing positionand another of said rollers engaged between said one roller and saidballs in load bearing position.
 13. A bearing as in claim 12, saidhousing having relatively flat opposed surfaces, certain of said ballsprojecting through one of said surfaces and one of said plurality ofrollers in the respective path of said projecting balls projectingthrough the opposed surface.
 14. A bearing as in claim 11, said housingcomprising a retainer and a sleeve connected for conjoint rotation andin which said paths are defined.
 15. A bearing as in claim 11, saidhousing comprising a retainer in which said paths are defined, and asleeve rotatably connected to said retainer.
 16. A bearing as in claim11, said one roller for each of said ball paths having a tapered endengaged by said balls in their respective ball paths as said balls moveinto and out of load bearing position.
 17. A bearing as in claim 11, thelongitudinal axis of said one roller being intersected by the load pathvector extending through the points of contact of said balls with saidone roller and the workpiece for the bearing when said balls are in theload bearing position.
 18. A bearing comprising a housing having twosubstantially flat surfaces and a retainer means defining an endlessbearing path, said path including load bearing and non-load bearingportions, a plurality of first bearing elements, a plurality ofrotatable second bearing elements, said first bearing elements beingmovable in said bearing path between a load bearing position whereinthey project from one of said housing surfaces and a non-load bearingposition, and one of said second bearing elements being engaged betweensaid first bearing elements in load bearing position and another of saidsecond bearing elements having a surface thereof projecting from theother of said housing surfaces, said one second bearing element beingfree of engagement with said first bearing elements in the non-loadbearing position.
 19. In a bearing, a housing, an endless bearing pathdefined in said housing, said path including an active portion and aninactive portion, a plurality of first bearing elements movable in andalong said bearing path between said active portion wherein the same arein load bearing position and said inactive portion wherein the same arein non-load bearing position, a second bearing element in said housing,and certain of said first bearing elements being in load bearingengagement with said second bearing element when said first bearingelements are in their load bearing position, said second bearing elementcomprising at least two freely rotatable roller bearing elements, one ofsaid two roller bearing elements being engaged between certain of saidfirst bearing elements in the load bearing position and the other ofsaid roller bearing elements.
 20. In a bearing as in claim 19, saidhousing having two relatively flat surfaces, certain of said firstbearing elements projecting through one of said surfaces and said otherof said second bearing elements projecting through the other of saidsurfaces.